New Holland ENG 1821 – Engine Control Module (ECM / ECU): Speed Sensor: Sensor 2 Out of Range (upper side)

The signal voltage or frequency from the secondary engine speed sensor (typically the camshaft position sensor or the secondary crankshaft sensor) is exceeding the maximum expected threshold, indicating a short to power in the wiring harness, an open circuit, or an internal failure within the sensor itself.

• L213
• L216
• L218
• L220
• L225
• L230
• L234
• C227
• C232
• C238
• B95B
• B95C
• B100B
• B110B
• B115B
• T4
• T5
• T6
• T7
• T9
• T9.390
• T9.600
• T9.700
• TL80A
• TL90A
• TL100A

1. 1

   Inspect the wiring harness between Speed Sensor 2 and the Engine ECU for chafed wires causing a short to a 12V/5V power source, or a disconnected/corroded connector causing an open circuit.

2. 2

   Disconnect the sensor and use a multimeter to test its internal resistance. It should measure between 109.5 - 143.5 Ω at 20 °C (68.0 °F). If it reads out of this range or shows infinite resistance, the sensor is defective.

3. 3

   Check the sensor air gap using a dial indicator or feeler gauge. The gap between the sensor tip and the timing gear/flywheel hub should be approximately 0.7 - 1.7 mm (0.0276 - 0.0669 in).

4. 4

   Inspect the timing gear or flywheel hub teeth for damage, missing teeth, or debris buildup that could disrupt the magnetic pulse.

1. 1

   Preparation

   Park the machine on a level surface, lower any attachments to the ground, turn off the engine, and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Locate the Sensor

   Locate Engine Speed Sensor 2. Depending on the specific engine block (ISM-IDI or FPT), this is typically mounted on the flywheel housing or the front timing gear cover.

3. 3

   Removal

   Disconnect the electrical harness connector from the sensor. Remove the retaining bolt(s) securing the sensor to the housing. Carefully pull the sensor straight out of its mounting bore.

4. 4

   Cleaning

   Wipe the mounting surface clean. Ensure no dirt or debris falls into the engine housing.

5. 5

   Installation

   Insert the new speed sensor into the bore. If the sensor bracket is adjustable, set the air gap to the specified 0.7 - 1.7 mm before fully tightening.

6. 6

   Secure

   Tighten the mounting bolt to the OEM torque specification.

7. 7

   Reconnection

   Reconnect the electrical harness connector until it clicks into place.

8. 8

   Testing

   Reconnect the negative battery cable. Start the engine and use a New Holland diagnostic service tool (or the machine's onboard display) to clear the ENG 1821 fault code. Verify that the engine runs smoothly without throwing the code again.